Flag size calculator: the size by the height of the pole
Published Written by Flagpole Guides
This page is an English translation of the Portuguese original. Where the two versions differ, the Portuguese text is the original.
What flag goes with an 8-metre pole? How large are the module and the blue circle? The calculator answers from the height of the pole, using the rule in article 21 of Law 5,700 of 1 September 1971, the standard sizes in panos of 45 centimetres and the design in modules of article 5.
Calculator
How it works
The calculator shows three figures:
- Nearest standard size: the size in panos of 45 centimetres, from 1 to 7 panos in steps of half a pano, whose width is nearest to the middle of the range in article 21. Between two equally close sizes, it shows the smaller one. The length follows the proportion of 20 modules long for 14 wide in article 5, rounded to the centimetre.
- Width under article 21: the range between one seventh and one fifth of the height of the pole, which the law sets for public offices and military units when the flag is raised on a pole in the ground.
- Module and blue circle: the width divided into 14 modules (article 5(I)) and the diameter of the blue circle, with a radius of 3.5 modules (article 5(IV)).
The rule in article 21
Few flag laws relate the flag to the pole. Law 5,700 does so in article 21: at public offices and military units, when the flag is raised on a pole in the ground, its width is no more than 1/5 and no less than 1/7 of the height of the pole. The calculator takes the middle of this range as its reference, which is a width of about one sixth of the height.
The guide of the Brazilian manufacturer B&B Iluminação for poles of 6 to 12 metres reaches close results: it gives ideal heights of 7 metres for the 2.5-pano flag, 8 metres for 3 panos, 9 metres for 3.5 panos, 11 metres for 4 panos and 12 metres for 4.5 panos. Manufacturers may also suggest a smaller flag depending on the local wind and the strength of the pole; the guide to flagpole heights covers these factors.
Examples
| Height of pole | Range in art. 21 | Nearest standard size | Module | Blue circle |
|---|---|---|---|---|
| 5 m | 0.71 to 1.00 m | 2 panos, 0.90 × 1.29 m | 6.4 cm | 45 cm |
| 6 m | 0.86 to 1.20 m | 2.5 panos, 1.13 × 1.61 m | 8.0 cm | 56 cm |
| 8 m | 1.14 to 1.60 m | 3 panos, 1.35 × 1.93 m | 9.6 cm | 68 cm |
| 10 m | 1.43 to 2.00 m | 4 panos, 1.80 × 2.57 m | 12.9 cm | 90 cm |
| 12 m | 1.71 to 2.40 m | 4.5 panos, 2.03 × 2.89 m | 14.5 cm | 101 cm |
| 15 m | 2.14 to 3.00 m | 5.5 panos, 2.48 × 3.54 m | 17.7 cm | 124 cm |
| 20 m | 2.86 to 4.00 m | 7 panos, 3.15 × 4.50 m | 22.5 cm | 158 cm |
Manufacturers sometimes state half-pano sizes with slightly different rounding, such as 1.12 × 1.60 metres for 2.5 panos. The Federal University of Viçosa, in a 2020 purchasing specification, uses 1.13 × 1.61 metres.
The official types
The seven normal types of article 4, from 1 to 7 panos, are the whole numbers in the calculator’s range. The guide to flag sizes gives all the measurements, and the guide on the price of a flag covers what matters when buying one.
Frequently asked questions
How does the calculator choose the size of the flag?
It works out the range in article 21 of Law 5,700, a width between one seventh and one fifth of the height of the pole, and shows the standard size in panos of 45 centimetres whose width is nearest to the middle of that range. Between two equally close sizes, it shows the smaller one.
Does the rule in article 21 apply to private poles?
Article 21 speaks of public offices and military units, when the flag is raised on a pole in the ground. For other poles, it is the official reference available, and manufacturers reach similar values in their guides.
Why does the calculator show half-pano sizes?
Article 4 of the law sets seven normal types, from one to seven panos, but allows intermediate types, keeping the proportions. Manufacturers and public buyers use half panos, such as the 2.5-pano flag of about 1.13 × 1.61 metres.
What is the module the calculator shows?
Under article 5 of Law 5,700, the width of the flag is divided into 14 equal parts, called modules. All the other measurements of the design, such as the length of 20 modules and the blue circle with a radius of 3.5 modules, are worked out from it.
What about poles over 20 metres?
On a 20-metre pole, type 7, 3.15 × 4.50 metres, is still within the range of article 21. For taller poles, article 4 provides for larger extraordinary types, keeping the proportions, and the pole’s manufacturer can indicate a suitable flag for the project.
Sources
This guide is based on the following sources, most of them in Portuguese:
- Lei nº 5.700, de 1º de setembro de 1971 (artigos 4º, 5º e 21) – Presidência da República
- Datasheet Mastro para Bandeira (guia bandeira × mastro) – B&B Iluminação
- Projeto básico para aquisição de bandeiras e rosetas (Dispensa nº 74/2020) – Universidade Federal de Viçosa
Related guides
- Flag sizesThe official sizes of Brazil’s national flag in panos of 45 cm, the proportions in modules of article 5 and the relation between flag and pole.
- Flagpole heightsThe height of a flagpole in Brazil: the 1/7 to 1/5 rule of article 21, the heights manufacturers offer, the wind and what limits the height on a plot.
- Price of a flagWhat affects the price of a flag in Brazil: size in panos, fabric, embroidery or print, finish, the maker’s mark on the hoist and consumer rights.
- Flag typesThe flags used in Brazil: the national flag and its official types, the flags of the states and municipalities, Mercosur and the Presidential Standard.